#include "Stack.h" 

void StackInit(ST* ps)
{
	assert(ps);
	ps->a = (STDataType*)malloc(sizeof(STDataType) * 4);
	if (ps->a == NULL)
	{
		perror("malloc fail");
		exit(-1);
	}
	ps->capacity = 4;
	ps->top = 0;
}

void StackDestroy(ST* ps)
{
	assert(ps);
	free(ps->a);
	ps->a = NULL;
	ps->capacity = ps->top = 0;
}

void StackPrint(ST* ps)
{
	int i = 0;
	for (i = 0; i < ps->top; i++)
	{
		printf("%d ", ps->a[i]);
	}
	printf("\n");
}

void StackPush(ST* ps, STDataType x)
{
	assert(ps);
	if (ps->top == ps->capacity)
	{
		STDataType* tmp = (STDataType*)realloc(ps->a, sizeof(STDataType) * 2 * ps->capacity);
		if (tmp == NULL)
		{
			perror("realloc fail");
			exit(-1);
		}
		ps->a = tmp;
		ps->capacity *= 2;
	}
	ps->a[ps->top] = x;
	ps->top++;
}

void StackPop(ST* ps)
{
	assert(ps);
	assert(ps->top > 0);

	ps->top--;
}

STDataType StackTop(ST* ps)
{
	assert(ps);
	assert(!StackEmpty(ps));

	return ps->a[ps->top - 1];
}
 
bool StackEmpty(ST* ps)
{
	assert(ps);
	return ps->top == 0;
}

int StackSize(ST* ps)
{
	assert(ps);

	return ps->top;
}

